Computed tomographic assessment of atherosclerosis in ancient Egyptian mummies.

occurred within the first few weeks after spinal interbody fusion procedures assisted with BMP, have been clinically insignificant in some patients, but in others have resulted in serious complications (spacer subsidence, loss of correction, spacer dislodgement, and failure of spinal fusion). In the study by Tumialán et al, no end plate resorption was reported. In contrast, a study by Vaidya et al, using the same interbody spacer and even smaller doses of BMP, reported 100% incidence of end plate resorption, resulting in subsidence of disc space in 40.5% of cervical levels. Improved surgical technique was emphasized by Tumialán et al as a reason for lack of resorption in their study, avoiding cortical end plate violations and therefore preventing contact between BMP and cancellous vertebral body, which can lead to osteolysis. However, a study by Slosar et al confirmed end plate violation during lumbar interbody fusions (interbody spacers were placed slightly deep and angulated) assisted with an even higher dose of BMP; no resorption and no subsidence was reported. Besides dosing and containment of BMPs in spinal fusion procedures, there are other unidentified causes of important discrepancies in reported results, incidences of adverse effects, and clinical consequences. We agree with Cahill et al on the need for refined guidelines for BMP use and further study of the long-term risks and benefits of BMP.